After returning to the United States, the squadron was reorganized and assigned to Rockwell Field, near San Diego in September 1919.

Between 1919 and 1922 the squadron frequently moved between bases in California and Oregon with detachments deployed locally to meet operational needs.

The 91st was reassigned to Wheeler-Sack Army Airfield in upstate New York in September 1941, where it became an observation squadron for the 4th Armored Division.

In order to prepare for possible hostilities in its own backyard, the military planners needed accurate charts and maps of all of these regions.

These operations, mainly aerial mapping, also included intelligence work, providing the United States with a storehouse of cartographic data on these regions that is still in use today.

As one of the best equipped photo reconnaissance units in the USAF, General MacArthur quickly called on the 91st to join the Far East Air Forces (FEAF) fighting on the Korean peninsula.

In addition to bomb damage assessment, targeting and aerial photography for the Bomber Command and FEAF, the 91st conducted Electronic Intelligence (ELINT) and "ferret" missions in theater mapping radar emissions of air defense sites.

An example of this type of work was reconnaissance missions which were conducted over Karafuto following reports that the Soviets had built extensive underground installations and missile-launching facilities on the island.

Shortly after the Korean Armistice Agreement, On 29 July 1953 a 343d Reconnaissance Squadron RB-50 temporarily attached to the 91st was shot down by Soviet fighters about ninety miles south of Vladivostok.

[5] the 91st was withdrawn from the Pacific and returned to the United States and to Great Falls Air Force Base, Montana on 20 December 1954.

Elements of the squadron remained with the Fifth Air Force in Japan to provide FEAF with a strategic reconnaissance and intelligence gathering capability.

Returning to the United States in late 1954, the 91st was tasked with experimenting with parasite fighters to provide long-range escort for B-36 Peacemaker strategic bombers on intercontinental missions.

A lesson learned from the Korean War was that American aircraft were often not able to outrun enemy fighters sent up to shoot or force them down.

The only major differences were the RF-84K's retractable hook in the upper part of the nose, rods on either side behind the cockpit, and downward angled horizontal stabilizers (to fit inside the GRB-36's bomb bay).

For the next year, pilots of the 91st successfully flew their RF-84Ks, but they experienced many near disasters while separating or hooking back up to the GRB-36 carrier aircraft.

This article incorporates public domain material from the Air Force Historical Research Agency